Luminous paint.



UNITED sTATEs PATENT OFFICE.

GUsTAv AUGUsTUs HENRY MULLER, or MoNTaEAL, QUEBEG; CNADA.

LUMINOUS PAINT.

No Drawing.

To all 'whom z't may concern.'

Be it known that I, GUsTAv AUGUSTUS HENRY MULLER, a suoe'ct of the King of Great Britain, and resident of 138 Milton street, in the city of Montreal, Province of Quebec, Dominion of Canada, have invented new and useful Improvements in Luminous `Paints, of which the following is the specification.

The invention relates to improvements in luminous paints and the objects of the invention are to furnish a paint that will readily add to its luminosity by absorption during the daylight, so as to throw out strikling and particularly distinct days of light in the darkness, to provide coloring -ei'ects for ornamentation purposesduring the daytime Without in any way minimizing the luminous properties of the paint at night and generally to make a cool` luminant comparatively cheap to,k produce and very eiiicient in use, and it conslsts essentially of the ingredients mixed in the manner described in or about the proportions named and in the arrangements pointed out in the claims for novelty following.` i

.In` the manufacture of the luminous substance, the first step is one taken in most processes that of calcining clean white shells at a strong red heat and producing a causn tic lime base, then two and one quarter pounds of caustic lime are boiled with one poundof sulfur in four gallons of water.

This is set asidein a covered vessel-for a 'few days; then the liquid is poured olf and the clear orange colored crystals are collected and let drain and `dried on bibulous paper. The: dried sulid is then placed in a clean graphite crucible provided with aco'ver 40 and heated for one half hour just short of redness and quickly for fifteen' minutes at white heat, a small (fuantity of pure calcium fluorid being added to the sulid before heating. The cover is then removed and the contents left in a clay retort until perfectly cold. The calcium luorid, so added to the sulfid, hasthe effect of removing impurities fromsaid sulfid such as soda or potash re.

maining lafter the treatment of the shells. The iluorin during the heating combines ucts which are drivenotf bythe heat, leaving the calcium to unite with sulfur, and thereby add more of the luminous compoundit'o the product.

Specification of Letters Patent.

I Application led June 8, 41916. Serial No. 102,505.

This luminous calcium sulfid is then mixed with various pigments and with barium sulfate. For different colors, the proportions vary also the ingredients to some eX- tent, as for instance to produce blue, the base luminous calcium suli'd is mixed with barium sulfate and the pigments, ultramarine blue and cobalt blue.

' For gray it is mixed with barium sulfate, Y calcium carbonate, ultramarine blue and sulid zinc.

For ygreen it is mixed with barium sulfateand green oxid chromium. r

For red it is mixedy with barium sulfate, madder lake and realgar.

' For yellow it is mixed with barium sulfate and barium chromate.

In other colors the ingredients are somewhat different of course, though broadly similar to the mixturesr described.

The proportions vary according to the color;-however the barium sulfate runs about six to ten parts andthe pigments from 5 to Y y 8 according to thel color and shade of color Wanted. 80

The mixing of the base and coloring adjuncts 'may lbe accomplished in more than one Way, such as roasting together or in any other manner that will insure a 'thorough intermingling of the parts.

. What Iv claim is :w

1. Iny luminous paints, a base ofv luminous calciuinsulfd produced by the treatment of caustic lime with sulfur and the subsequent heating with an' agent which reacts with 90 matter foreign to the calcium sulfid to form volatile compounds which aredriven off by the heat.

2. In luminous paints, a base of luminous vcalcium sulfid produced by the treatment of '95 caustic lime with sulfur and subsequent heating with calcium fl-uorid.r

3'. In luminouspaints, abase of luminousvcalcium producedr by the 'treatment of caus- `tic lime with sulfur and subsequent purili- 10Q cation by heating with calcium luorid, and adiuncts mixed with said base for coloring purposes. v i

Signed at the city of Montreal, in Canada,

this 6th` day of June, 1916.vv with `such impurities forming volatilelprod-` leusrirweusrus waarnemen Vilitnessesz' il A J. FETHEnsToNBAUeH, Grenen D.` Qumran. 

